Yeah! Mostly likely kaname and Yuuki would end up together... it was pretty much said in the description and how the anime goes... Kaname was the first one who appears first in Yuuki's life. the percentage for Zero and Yuuki would be 25% compared to Kaname and Yuuki who is 75% and also if you have notice that in the synapsis provided, it stated ' Is Kaname's infatuation with Yuki the beginning of a forbidden romance, or is it something in her forgotten past that draws him to her. '
I've read the manga and both her past and her love for Kaname draws him to her and I've also notice that the way Yuuki treats Zero is mostly likely to be brother-sister relationship. Also Zero, stated in the description, is destined to become a level E vampire... though he drinks Kaname's blood, it was just to slow his progression.

No hard feelings though... it was just a theory I've investigated...

It clearly says that I am a rooted fan for Kaname Kuran...

but anyways...

it was just a theory so don't get the wrong idea for all ZeroxYuuki fans :D